Vacuum processing method and vacuum processing apparatus

ABSTRACT

A vacuum processing apparatus produces fluorine radicals by activating a fluorinating gas containing at least fluorine atoms and fluorinates the surface of a component formed of an organic material ( 32 ) exposed to an atmosphere of a processing chamber ( 2 ) before carrying an object (S) into the processing chamber ( 2 ). The object (S) is carried into the processing chamber ( 2 ) after the completion of a fluorinating process. The object (S) is processed with a processing gas containing at least oxygen radicals. Etching of the component formed of the organic material ( 32 ) can be prevented by the fluorination of surface of the component formed of the organic material ( 32 ) and exposed to an atmosphere in the processing chamber ( 2 ).

TECHNICAL FIELD

[0001] The present invention relates to a vacuum processing method usingoxygen radicals for processing an object to be processed in a processingchamber defined by a vacuum vessel, and a vacuum processing apparatusfor carrying out the same.

BACKGROUND ART

[0002] Semiconductor wafers for fabricating ICs and glass substrates forliquid crystal displays, etc. (hereinafter referred to as “object to beprocessed” or “object”) are processed by a process, such as an etchingprocess or an ashing process, by a vacuum processing method using avacuum processing apparatus. The vacuum processing method and the vacuumprocessing apparatus place an object in a processing chamber defined bya vacuum vessel and process the object in an evacuated atmosphere.

[0003] Conventional vacuum processing methods and apparatus for carryingout the same include a chemical dry etching (CDE) method and anapparatus for carrying out the same which produce radicals in a plasmaproducing chamber separated from a processing chamber by activating aprocess gas, and introduce the radicals into the processing chamber toetch a thin film formed on a surface of the object placed in theprocessing chamber with the radicals.

[0004] Conventional vacuum processing methods and apparatus for carryingout the same further include a reactive ion etching (RIE) method and anapparatus for carrying out the same which produce a plasma by applying aradio-frequency voltage to a process gas supplied into a processingchamber, and etch an object placed in the processing chamber with theplasma produced in the processing chamber, and a microwave plasmaetching method and an apparatus for carrying out the same which producea plasma by exciting a process gas supplied into a processing chamber byapplying a microwave to the process gas, and etch an object placed inthe processing chamber with the plasma.

[0005] When an object is processed with oxygen radicals by theconventional vacuum processing method and the apparatus for carrying outthe same, organic structural members and organic adhesives are etched ifthey are exposed to oxygen radicals in the processing chamber.

[0006] Referring to FIG. 6, an electrostatic chuck 28 for fixedlyholding an object is placed on a support surface 3 a of an objectsupport table 3 place in a processing chamber. The electrostatic chuck28 has an electrode sheet 29, and electrode covering sheets 30sandwiching the electrode sheet 29 therebetween.

[0007] The electrode covering sheets 30 are formed of a heat-resistantpolymer, i.e., an organic material, such as a polyimide. The lowerelectrode covering sheet 30 is bonded to the support surface 3 a of theobject support table 3 with an organic adhesive 32.

[0008] Since the electrode covering sheets 30 and the adhesive 32 areformed of organic materials, portions of the electrode covering sheets30 and the adhesive 32 exposed to an atmosphere in the processingchamber are etched by oxygen radicals for processing the object.

[0009] Since the components formed of organic materials and exposed tothe atmosphere in the processing chamber are etched by oxygen radicals,the components of the vacuum processing apparatus, such as theelectrostatic chuck, are short-lived and are sources of particles thatreduces the yield of products. Essentially, the vacuum processingapparatus using oxygen radicals must avoid using organic materials.However, the use of parts formed of organic materials in such an vacuumprocessing apparatus is unavoidable in the present circumstances becauseof requirements for machining parts or for the common use of parts.

[0010] Accordingly, it is an object of the present invention to providea vacuum processing method and an apparatus for carrying out the samecapable of preventing the etching of parts formed of organic materialsand exposed to an atmosphere in a processing chamber even when an objectis processed with oxygen radicals.

DISCLOSURE OF THE INVENTION

[0011] According to the present invention, a vacuum processing method ofprocessing an object to be processed with an oxygen radical in aprocessing chamber defined by a vacuum vessel of a vacuum processingapparatus comprises the steps of: fluorinating a surface of a componentformed of an organic material and exposed to an atmosphere in theprocessing chamber with a fluorine radical produced by activating afluorinating gas containing at least a fluorine atom with the vacuumprocessing apparatus before carrying the object into the processingchamber; carrying the object into the processing chamber; and processingthe object with the oxygen radical produced by activating a process gascontaining at least an oxygen atom.

[0012] The term ‘radical’ as used in the description denotes achemically highly active atom or molecule. Sometimes, radicals arereferred to as ‘active species’.

[0013] Preferably, the vacuum processing apparatus comprises an objectsupport table disposed in the processing chamber to support the objectthereon, and an electrostatic chuck mounted on a surface of the objectsupport table to hold the object on the object support table, and theelectrostatic chuck comprises an electrode, and an electrode coveringsheet covering the electrode. Theorganic material is that forming theelectrode covering sheet and an organic adhesive bonding theelectrostatic chuck to the surface of the object support table.

[0014] Preferably, the vacuum processing apparatus comprises an objectsupport table disposed in the processing chamber to support the objectthereon, an electrostatic chuck mounted on a surface of the objectsupport table to hold the object on the object support table, and aprotective sheet of a fluororesin covering the electrostatic chuck toprotect the same. The organic material includes an organic adhesive usedto bond the protective sheet.

[0015] Preferably, the fluorinating gas is a mixed gas including a gascontaining at least a fluorine atom and an O₂ gas.

[0016] Preferably, the gas containing at least a fluorine atom is one ofCF₄, C₂F₆, C₃F₈, NF₃ and SF₆, or a mixture of some of these gases.

[0017] Preferably, a ratio of a flow rate of the O₂ gas to a flow rateof the fluorinating gas including the O₂ gas is 40% or below.

[0018] Preferably, the process gas contains at least an O₂ gas.

[0019] Preferably, the process gas and the fluorinating gas areactivated in a plasma producing chamber separated from the processingchamber, and the fluorine radical or the oxygen radical is supplied intothe processing chamber.

[0020] Preferably, the object processing step processes the plurality ofobjects successively, and the fluorinating step is performed after theobject processing step, and the object processing step and thefluorinating step are repeated alternately.

[0021] The vacuum processing method according to the present inventionfluorinates the component formed of organic material and exposed to theatmosphere in the processing chamber with the fluorine radical, and thenprocesses the object with the oxygen radical. Fluorinated surface layerof the organic component serves as protective film to prevent theetching of the component formed of the organic material with an oxygenradical.

[0022] A vacuum processing apparatus according to the present inventioncomprises: a vacuum vessel defining a processing chamber to beevacuated; radical producing means for producing a fluorine radical byactivating a fluorinating gas including at least a fluorine atom and forproducing an oxygen radical by activating a process gas containing atleast an oxygen atom; gas supply means for supplying the fluorinatinggas or the process gas to the radical producing means; and an objectsupport table disposed in the processing chamber to support an object tobe processed thereon; wherein a surface of a component formed of anorganic material and exposed to an atmosphere in the processing chamberis fluorinated by the fluorine radical, and then the object is mountedon the object support table and processed with the oxygen radical.

[0023] A vacuum processing apparatus according to the present inventioncomprises: a vacuum vessel defining a processing chamber to beevacuated; radical producing means for producing an oxygen radical byactivating a process gas containing at least an oxygen atom; a gassupply means for supplying the process gas to the radical producingmeans; an object support table disposed in the processing chamber tosupport an object to be processed thereon; an electrostatic chuckmounted on a surface of the object support table to hold the object onthe object support table; and a protective sheet formed of a fluororesinand covering the electrostatic chuck to protect the electrostatic chuck.

[0024] Preferably, a surface of a component formed of an organicmaterial and exposed to an atmosphere in the processing chamber isfluorinated with a fluorine radical produced by activating afluorinating gas containing at least a fluorine atom with the radicalproducing means.

[0025] Preferably, the fluorinating gas is a mixed gas including a gascontaining at least a fluorine atom and an O₂ gas.

[0026] Preferably, the gas containing at least a fluorine atom is one ofCF₄, C₂F₆, C₃F₈, NF₃ and SF₆, or a mixture of some of these gases.

[0027] Preferably, a ratio of a flow rate of the O₂ gas to a flow rateof the fluorinating gas including the O₂ gas is 40% or below.

[0028] Preferably, the process gas contains at least an O₂ gas.

[0029] Preferably, the radical producing means has a plasma producingchamber separated from the processing chamber, and the radical producedin the plasma producing chamber is supplied into the processing chamber.

[0030] Preferably, a cycle of fluorinating a component formed of anorganic material and exposed to an atmosphere in the processing chamberand successively processing a plurality of objects is repeated.

[0031] The vacuum processing apparatus according to the presentinvention fluorinates the surface of the component formed of the organicmaterial and exposed to the atmosphere in the processing chamber withthe fluorine radical, and then processes the object with the oxygenradical. The fluorinated surface layer of the component serves asprotective film to prevent the etching of the component formed of theorganic material with the oxygen radical.

[0032] The vacuum processing apparatus according to the presentinvention is provided with the protective sheet of a fluororesincovering the electrostatic chuck. Therefore, the etching of theelectrostatic chuck with the oxygen radical can be prevented by theprotective sheet covering the electrostatic chuck.

BRIEF DESCRIPTION OF THE DRAWINGS

[0033]FIG. 1 is a schematic, longitudinal sectional view of chemical dryetching system (CDE system), i.e., a vacuum processing apparatus, in apreferred embodiment according to the present invention;

[0034]FIG. 2 is an enlarged, fragmentary, schematic longitudinalsectional view of an object support table included in the vacuumprocessing apparatus shown in FIG. 1;

[0035]FIG. 3 is a table showing the results of comparative experimentsconducted to demonstrate the protective effect of fluorination onprotecting organic components;

[0036]FIG. 4 is a graph showing etching rate, and O/F radical ratiodetermined by emission spectral analysis when a component formed of anorganic material is etched with a mixed gas containing CF₄ and O₂;

[0037]FIG. 5 is a graph showing the dependence of fluorinating rate onO₂/(O₂+CF₄) flow rate ratio when an organic film is fluorinated with amixed gas containing CF₄ and O₂ by the CDE system shown in FIG. 1; and

[0038]FIG. 6 is an enlarged, fragmentary, schematic longitudinalsectional view of an object support table included in a conventionalvacuum processing apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION

[0039] A vacuum processing method and an apparatus for carrying out thesame embodying the present invention will be described hereinafter withreference to the accompanying drawings.

[0040]FIG. 1 shows a downflow chemical dry etching system (CDE system)as an example of a vacuum processing apparatus for carrying out a vacuumprocessing method embodying the present invention.

[0041] Referring to FIG. 1, the CDE system has a vacuum vessel 1defining a processing chamber 2, and an object support table 3 disposedin the processing chamber 2. A object S is supported on the objectsupport table 3. The object support table 3 is provided with atemperature regulator, not shown.

[0042] The temperature of the object S can be regulated by thetemperature regulator.

[0043] The vacuum vessel 1 has a bottom wall 4 provided with gas outletopenings 5. Each of discharge pipes 6 has one end connected to a vacuumpump, not shown, and the other end connected to the outlet opening 5.The vacuum vessel 1 has a top wall 7 provided with a gas inlet opening8. A gas supply pipe 9 formed of a fluororesin is connected to the gasinlet opening 8. A quartz pipe 10 has one end connected to the gassupply pipe 9 and the other end sealed by a sealing member 11 internallyprovided with a gas passage 19. A gas supply pipe 18 has one endconnected to the sealing member 11 and the other end connected to branchpipes 20 and 21.

[0044] The branch pipes 20 and 21 are connected to a first gas cylinder23 provided with a first flow regulating valve 22 and a second gascylinder 25 provided with a second flow regulating valve 24,respectively. The first gas cylinder 23 and the second gas cylinder 25constitute a gas supply source (gas supply means) 26.

[0045] The first gas cylinder 23 contains a gas containing at leastfluorine atoms, preferably, one of CF₄, C₂F₆, C₃F₈, NF₃ and SF₆, or amixture of some of these gases. The second gas cylinder 25 contains agas containing at least oxygen atoms, preferably, a gas containing atleast O₂ gas.

[0046] A plasma producing device (radical producing means) 13 providedwith a waveguide 12 is combined with the quartz pipe 10 so as tosurround a section of the quartz pipe 10. A plasma producing chamber 14is formed in the section of the quartz pipe 10 surrounded by the plasmaproducing device 13. A microwave generator 27 is connected to thewaveguide 12.

[0047] A shower plate 16 provided with a plurality of gas jetting holes17 is placed in the processing chamber 2 so as to form a gas storagechamber 15 above the processing chamber 2 to distribute radicalssupplied into the processing chamber 2 uniformly over the entire surfaceof the object S.

[0048]FIG. 2 is an enlarged, fragmentary, schematic longitudinalsectional view of the object support table 3 of the CDE system shown inFIG. 1. As shown in FIG. 2, an electrostatic chuck 28 for fixedlyholding the object S by electrostatic attraction is placed on a supportsurface 3 a of the object support table 3. The electrostatic chuck 28has an electrode sheet 29 of a conductive material, such as copper, andelectrode covering sheets 30 sandwiching the electrode sheet 29therebetween. The electrode covering sheets 30 are formed of aheat-resistant polymer, i.e., an organic material, such as a polyimide.The lower electrode covering sheet 30 is bonded to the support surface 3a of the object support table 3 with an organic adhesive 32.

[0049] The electrostatic chuck 28 is covered with a protective sheet 31.Preferably, the protective sheet 31 is formed of a fluororesin. Sincethe electrode covering sheets 30 of an organic material are covered withthe protective sheet 31, the erosion of the surfaces of the electrodecovering sheets 30 by the etching action of oxygen radicals which areused for etching the object S can be processed.

[0050] The protective sheet 31 is bonded to the surface of the upperelectrode covering sheet 30 of the electrostatic chuck 28 and to aperipheral region of the support surface 3 a of the object support table3 with the organic adhesive 32. The peripheral surface 33 of the layerof the organic adhesive 32 is exposed to an atmosphere in the processingchamber 2 (FIG. 1). Therefore, the peripheral surface 33 of the layer ofthe organic adhesive 32 is subject to erosion by etching while theobject S is processed with oxygen radicals unless the some measures aretaken to protect the peripheral surface 33.

[0051] Some parts of components formed of organic materials are exposed,for example, on the inner surface of the vacuum vessel 1 in addition tothe peripheral surface 33 of the layer of the organic adhesive 32.

[0052] The vacuum processing method and the apparatus embodying thepresent invention evacuates the vacuum vessel 1 to a vacuum (reducedpressure) by removing gases and vapors through the outlet openings 5 andthe discharge pipes 6 by the vacuum pump before carrying the object Sinto the processing chamber 2.

[0053] The gas containing at least fluorine atoms is supplied from thefirst gas cylinder 23 through the branch pipe 20, the gas supply pipe 18and the gas passage of the sealing member 11 into the quartz pipe 10. Atthe same time, the gas contained at least oxygen atoms is supplied fromthe second gas cylinder 25. The first flow regulating valve 22 and thesecond flow regulating valve 24 are adjusted so that the gas containingat least fluorine atoms and the gas containing at least oxygen atoms aresupplied at flow rates and flow rate ratios suitable for fluorinatingthe organic components.

[0054] Microwaves generated by the microwave generator 27 are guided bythe waveguide 12 of the plasma producing device 13 into the plasmaproducing chamber 14. Consequently, glow discharge is generated in theplasma producing chamber 14 and a plasma P is produced, whereby fluorinecontained in the mixed gas for fluorination is excited and fluorineradicals are produced.

[0055] The fluorinating gas containing fluorine radicals is suppliedthrough the quartz pipe 10, the gas supply pipe 9 and the gas inletopening 8 into the gas storage chamber 15. Then, the fluorinating gas isjetted from the gas storage chamber 15 through the gas jetting holes 17so as to be uniformly distributed in the processing chamber 2 bypressure difference between the gas storage chamber 15 and theprocessing chamber 2.

[0056] Fluorine radicals thus supplied into the processing chamber 2fluorinate, for example, the peripheral surface 33 of the layer of theorganic adhesive 32, i.e., a surface of an organic component exposed toan atmosphere in the processing chamber 2. The fluorinating gas reactedwith the peripheral surface 33 of the layer of the organic adhesive 32is discharged through the gas outlet openings 5 and the discharge pipes6 by the vacuum pump.

[0057] Such a fluorinating process is continued for a time necessary toform a fluorinated film of a desired thickness. Then, the supply of thegases from the first gas cylinder 23 and the second gas cylinder 25 isstopped, and the object S is carried into the processing chamber 2.Subsequently, the gas containing at least oxygen atoms is suppliedthrough the branch pipe 21, the gas supply pipe 18 and the gas passage19 of the sealing member 11 into the quartz pipe 10. At the same time,the gas containing at least fluorine atoms is supplied from the firstgas cylinder 23. The first flow regulating valve 22 and the second flowregulating valve 24 are adjusted so that the gas containing at leastfluorine atoms and the gas containing at least oxygen atoms are suppliedat flow rates and flow rate ratios suitable for etching the object S.

[0058] Microwaves generated by the microwave generator 27 are guided bythe waveguide 12 of the plasma producing device 13 into the plasmaproducing chamber 14. Consequently, glow discharge is generated in theplasma producing chamber 14 and a plasma P is produced, whereby oxygencontained in the process gas, i.e., a mixed gas of the gas containing atleast oxygen atoms and the gas containing at least fluorine atoms, isexcited and oxygen radicals are produced.

[0059] The process gas containing oxygen radicals is supplied throughthe quartz pipe 10, the gas supply pipe 9 and the gas inlet opening 8into the gas storage chamber 15. Then, the process gas is jetted fromthe gas storage chamber 15 through the gas jetting holes 17 so as to beuniformly distributed in the processing chamber 2 by pressure differencebetween the gas storage chamber 15 and the processing chamber 2. oxygenradicals thus supplied into the processing chamber 2 reacts with a thinfilm formed on a surface of the object S to etch the thin film by anetching process. The process gas reacted with the thin film formed onthe surface of the object S is discharged through the gas outletopenings 5 and the discharge pipes 6 by the vacuum pump.

[0060] The oxygen radicals supplied into the processing chamber 2 reach,for example, the peripheral surface 33 of the layer of the organicadhesive 32, i.e., a surface of an organic component exposed to theatmosphere of the processing chamber 2. However, the etching of theperipheral surface 33 of the layer of the organic adhesive 32 and thelike by the oxygen radicals is limited to the least unavoidable extentand are etched very little because the peripheral surface 33 of thelayer of the organic adhesive 32 and the like are fluorinatedbeforehand.

[0061] The etching process stopped after successively etching several orseveral tens of objects S, and the fluorinating process is performedafter removing the last object S from the object support table 3 tofluorinate the surfaces of the organic components again. Then, theetching process is resumed. Thus, the fluorinating process and theetching process are repeated alternately to process several or severaltens of objects S successively after fluorinating the surfaces of theorganic components.

[0062] Although the embodiment has been described as applied to theetching process for etching objects, the embodiment is applicable alsoto an ashing process.

[0063] Preferably, the fluorinating gas is one of CF₄, C₂F₆, C₃F₈, NF₃and SF₆, or a mixture of some of these gases.

[0064] Preferably, the process gas is a gas containing at least O₂ gas.

[0065] Although the electrostatic chuck 28 of the vacuum processingapparatus in the foregoing embodiment is covered with the protectivesheet 31, the present invention may be embodied by a vacuum processingmethod and an apparatus provided with the electrostatic chuck 28 notcovered with any sheet corresponding to the protective sheet 31.

[0066] When the object support table 3 as shown in FIG. 6 is employed,the surface of the electrode covering sheet 30 formed of an polyimideand the exposed surface of the layer of the organic adhesive 32 arefluorinated by a fluorinating process similar to that described abovebefore an object S is mounted on the object support table 3.

[0067] Thus, the etching of the electrode covering sheet 30 and thesurface of the layer of the organic adhesive 32 with oxygen radicals canbe prevented in the etching process for etching the object S with oxygenradicals.

[0068]FIG. 3 shows the results of comparative experiments conducted byusing the CDE system shown in FIG. 1 to demonstrate the protectiveeffect of the fluorinating process on protecting organic components.Wafers provided with a carbon film, i.e., an organic film, was used assamples. Although the experiments demonstrate the effect of thefluorinating process on the organic films formed on the surfaces of thewafers, the effect holds true for the organic components of the walls ofthe vacuum vessel 1 and the object support table 3, such as the layer ofthe organic adhesive and the sheet of a polyimide.

[0069] In FIG. 3, the result of experiments in which the fluorinatingprocess was omitted and the sample wafer was subjected to an etchingprocess for 60 min is shown in an upper section. The etching processused an etching gas containing one part CF₄ gas and three parts O₂ gasand microwaves of 450 W in power. The processing chamber 2 was evacuatedat 40 Pa and the object support table 3 was kept at 5° C. The carbonfilm was etched by a depth of 3.9 μm.

[0070] The result of experiments in which the sample wafer was subjectedto the fluorinating process and the same etching process of theforegoing conditions is shown in a lower section in FIG. 3. Thefluorinating process used a mixed gas containing three parts CF₄ gas andone part O₂ gas. The etching process used an etching gas containing onepart CF₄ gas and three parts O₂ gas and microwaves of 700 W in power.The processing chamber was evacuated at 40 Pa and the object supporttable 3 was kept at 5° C. for the fluorinating process. After thefluorinating process, the sample wafer was subjected to the etchingprocess.

[0071] The carbon film was etched by a depth of only 0.5 μm, whichproved the great effect of fluorination on the suppression of etching ofthe carbon film by oxygen radicals.

[0072]FIG. 4 is a graph showing etching rate, and O/F radical ratiodetermined by emission spectral analysis when a film of an organicmaterial was etched with a mixed gas containing CF₄ and O₂ In FIG. 4,0₂/(0 ₂+CF₄) flow rate ratio, i.e., the ratio of the flow rate of O₂ gasto the flow rate of the mixed gas (0 ₂+CF₄), is measured on thehorizontal axis.

[0073] As obvious from FIG. 4, the O/F radical ratio, i.e., the ratio ofthe amount of oxygen radicals to that of fluorine radicals produced, andetch rate at which the organic film is etched is increasing along withthe increase of O₂/(0 ₂+CF₄) flow rate ratio. When the O₂ /(O₂+CF₄) flowrate ratio is about 25% (CF₄ gas:O₂ gas=3:1), the organic film is etchedat a negligibly small etch rate. Therefore, when the fluorinatingprocess is carried out according to such conditions, etching of organiccomponents causes problems scarcely.

[0074]FIG. 5 is a graph showing the dependence of fluorinating rate onO₂/(O₂+CF₄) flow rate ratio, i.e., the ratio of flow rate of O₂ gas tothat of the mixed gas containing O₂ gas and CF₄ gas, when an organicfilm is fluorinated with the mixed gas containing CF₄ and O₂ by the CDEsystem shown in FIG. 1. As obvious from FIG. 5, the organic film isscarcely fluorinated when the O₂/(O₂+CF₄) flow rate ratio is greaterthan 40%.

[0075] When the mixed gas containing CF₄ and O₂ is used as afluorinating gas, a preferable O₂/(O₂+CF₄) flow rate ratio is notgreater than 40%.

[0076] As is apparent from the foregoing description, the vacuumprocessing method and the apparatus for carrying the same embodying thepresent invention fluorinate the surfaces of the organic componentsexposed to the atmosphere in the processing chamber 2 with fluorineradicals in the fluorinating process, and then etches the object S withoxygen radicals in the etching process. Therefore, etching of theorganic components with oxygen radicals can be prevented.

[0077] Since the electrostatic chuck 28 is covered with and protected bythe protective sheet 31 of a fluororesin, etching of the electrodecovering sheets 30 of the electrostatic chuck 28 with oxygen radicalscan be prevented.

[0078] Since the fluorinating process for fluorinating the organiccomponents can be achieved by the vacuum processing apparatus, anyspecial apparatus for the fluorination of the organic components isunnecessary, and the members requiring fluorination by the fluorinatingprocess need not be removed from the vacuum processing apparatus.

[0079] The present invention is not limited in its practical applicationto the foregoing CDE method and the CDE system, and is applicable tovarious vacuum processing methods and vacuum processing apparatus whichprocess objects in a vacuum atmosphere. More concretely, the presentinvention is applicable to dry etching methods and apparatus forcarrying out the same, such as reactive ion etching (RIE) methods andapparatus for carrying out the same and microwave plasma etching methodsand apparatus for carrying out the same, or ashing methods and apparatusfor carrying out the same.

INDUSTRIAL APPLICABILITY

[0080] The present invention can be applied to an etching/ashing processfor etching/ashing semiconductor wafers for fabricating ICs and glasssubstrates for liquid crystal displays.

1. A vacuum processing method of processing an object to be processedwith an oxygen radical in a processing chamber defined by a vacuumvessel of a vacuum processing apparatus, which comprises the steps of:fluorinating a surface of a component formed of an organic material andexposed to an atmosphere in the processing chamber with a fluorineradical produced by activating a fluorinating gas containing at least afluorine atom with the vacuum processing apparatus before carrying theobject into the processing chamber; carrying the object into theprocessing chamber; and processing the object with the oxygen radicalproduced by activating a process gas containing at least an oxygen atom.2. The vacuum processing method according to claim 1, wherein the vacuumprocessing apparatus comprises an object support table disposed in theprocessing chamber to support the object thereon, and an electrostaticchuck mounted on a surface of the object support table to hold theobject on the object support table; the electrostatic chuck comprises anelectrode, and an electrode covering sheet covering the electrode; andthe organic material includes both a material forming the electrodecovering sheet and an organic adhesive bonding the electrostatic chuckto the surface of the object support table.
 3. The vacuum processingmethod according to claim 1, wherein the vacuum processing apparatuscomprises an object support table disposed in the processing chamber tosupport the object thereon, an electrostatic chuck mounted on a surfaceof the object support table to hold the object on the object supporttable, and a protective sheet of a fluororesin covering theelectrostatic chuck to protect the electrostatic chuck; the organicmaterial includes an organic adhesive used to bond the protective sheet.4. The vacuum processing method according to any one of claims 1 to 3,wherein the fluorinating gas is a mixed gas including a gas containingat least a fluorine atom and an O₂ gas.
 5. The vacuum processing methodaccording to claim 4, wherein the gas containing at least a fluorineatom is one of CF₄ , C₂F₆, C₃F₈, NF₃ and SF₆, or a mixture of some ofthese gases.
 6. The vacuum processing method according to claim 4 or 5,wherein a ratio of a flow rate of the O₂ gas to a flow rate of thefluorinating gas including the O₂ gas is 40% or below.
 7. The vacuumprocessing method according to any one of claims 1 to 6, wherein theprocess gas contains at least an O₂ gas.
 8. The vacuum processing methodaccording to any one of claims 1 to 7, wherein the process gas and thefluorinating gas are activated in a plasma producing chamber separatedfrom the processing chamber, and the fluorine radical or the oxygenradical is supplied into the processing chamber.
 9. The vacuumprocessing method according to any one of claims 1 to 8, wherein theobject processing step processes a plurality of objects successively,and the fluorinating step is performed after the object processing step,and the object processing step and the fluorinating step are repeatedalternately.
 10. A vacuum processing apparatus comprising: a vacuumvessel defining a processing chamber to be evacuated; radical producingmeans for producing a fluorine radical by activating a fluorinating gasincluding at least a fluorine atom and for producing an oxygen radicalby activating a process gas containing at least an oxygen atom; gassupply means for supplying the fluorinating gas or the process gas tothe radical producing means; and an object support table disposed in theprocessing chamber to support an object to be processed thereon; whereina surface of a component formed of an organic material and exposed to anatmosphere in the processing chamber is fluorinated by the fluorineradical, and then the object is mounted on the object support table andprocessed with the oxygen radical.
 11. A vacuum processing apparatuscomprising: a vacuum vessel defining a processing chamber to beevacuated; radical producing means for producing an oxygen radical byactivating a process gas containing at least an oxygen atom; gas supplymeans for supplying the process gas to the radical producing means; anobject support table disposed in the processing chamber to support anobject to be processed thereon; an electrostatic chuck mounted on asurface of the object support table to hold the object on the objectsupport table; and a protective sheet formed of a fluororesin andcovering the electrostatic chuck to protect the electrostatic chuck. 12.The vacuum processing apparatus according to claim 10 or 11, wherein asurface of a component formed of an organic material and exposed to anatmosphere in the processing chamber is fluorinated with a fluorineradical produced by activating a fluorinating gas containing at least afluorine atom with the radical producing means.
 13. The vacuumprocessing apparatus according to claim 12, wherein the fluorinating gasis a mixed gas including a gas containing at least a fluorine atom andan O₂ gas.
 14. The vacuum processing apparatus according to claim 13,wherein the gas containing at least a fluorine atom is one of CF₄, C₂F₆,C₃F₈, NF₃ and SF₆, or a mixture of some of these gases.
 15. The vacuumprocessing apparatus according to claim 13 or 14, wherein a ratio of aflow rate of the O₂ gas to a flow rate of the fluorinating gas includingthe O₂ gas is 40% or below.
 16. The vacuum processing apparatusaccording to any one of claims 10 to 15, wherein the process gascontains at least an O₂ gas.
 17. The vacuum processing apparatusaccording to any one of claims 10 to 16, wherein the radical producingmeans has a plasma producing chamber separated from the processingchamber, and the radical produced in the plasma producing chamber issupplied into the processing chamber.
 18. The vacuum processingapparatus according to any one of claims 10 to 17, wherein a cycle offluorinating a component formed of an organic material and exposed to anatmosphere in the processing chamber and successively processing aplurality of objects is repeated.